The present invention relates broadly to the production of an apportioned meat product having a controlled volumetric size and weight.
The processing of meat, and especially of poultry, has burgeoned to where approximately four (4) billion chickens are processed and sold yearly in the United States alone. Indeed, the U.S. consumption of poultry has increased to where, for the first time in 1988, it exceeded that of beef. Such increase has been attributed to the recommendation of many medical groups that red meats be substituted with poultry or fish having a relatively lower percentage of saturated fats as a means of reducing overall serum cholesterol levels and the attendant risk of heat disease.
Spurred largely by consumer demand, producers of prepared and packaged foods, as well as restaurateurs, have been using more and more poultry, and have required suppliers to deliver products meeting stringent size and weight specifications. More recently restaurants, including the popular fast food chains, seeking to provide customers with a consistent and quality product, have tightened specifications not only as to uncooked size and weight ranges, but also as to cooking times and cooked sizes and weights. However, and particularly with respect to the bun-sized, whole-muscle chicken breast fillets presently favored by consumers as an alternative to hamburger patties, the processing industry has had difficulty meeting the tightened product specifications imposed by buyers.
Complicating the problems of meat processors in meeting the product specifications of the buyers, is that the hatcheries which supply the broiler-sized chickens for processing have moved toward raising larger birds for improved slaughtering productivity. The restaurants and other buyers of the sized product, however, have not adjusted their size and weight requirements accordingly. Meat processors therefore are faced with having to apportion a cut of meat which is both thicker and larger than those previously available.
Machines for the automated portioning of whole muscle meat products such as poultry breasts have been proposed. For example, U.S. Pat. No. 4,941,379 describes an apparatus for trimming poultry meat to a select size, shape, and weight. The apparatus includes a support frame upon which is mounted a plurality of mandrels aligned in a side-by-side relationship for movement in a continuous path along the frame. Each mandrel has a sizing chamber adapted to receive a given size and volume of a poultry breast cut through a top opening thereof. The sizing chamber is formed as having front and rear walls which are yieldably connected, with means being provided along the continuous path of the mandrel to compress the walls assuring a consistent sizing chamber volume. The mandrels are loaded at a given point along the path for movement past a cutting station which automatically trims any excess meat extending beyond the confines of the sizing chamber. After trimming, the front wall of the sizing chamber is released to return to its original position. The mandrel then continues along the defined path and is inverted as it approaches an unloading station where means are provided for urging the sized meat portion out of the sizing chamber.
Assuming a fixed muscle density of the meat and a consistent volumetric capacity of the sizing chamber, meat portions of a uniform weight may be obtained. However, as the meat is not irreversibly compressed within the sizing chamber sufficient to overcome the inherent orientation memory of the muscle fibers, the portions have been observed to contract after trimming to return somewhat to their original, uncut dimensions. Further contraction of the muscle fibers has been seen during cooking wherein the protein in the muscle tissue is heat denatured. The result is a product having piece to piece size and thickness variations which defies attempts to implement effective cooking schedules.
Moreover, the apparatus described in U.S. Pat. No. 4,941,379 alters the meat in only two dimensions, i.e., length and width, both in a single plane. As the meat to be portioned increases in overall size in three dimensions, however, the cut portion thereof, having been sized only in two dimensions, manifests a corresponding increased thickness. Again, although meat portions of a uniform weight may be obtained, consistency as to uniformity of size and thickness may not necessarily be achieved.
Some poultry breast processors have attempted to control the thickness dimension of the product by first making an axial cut through a cross section of a horizontal plane parallel to the fascia of the meat. The meat then is handled a second time for sizing. Other processors first pass the meat through a meat press and/or scarifier, which likewise involves a second handling step.
Another machine proposed for the automated sizing of whole muscle meat products employs a reciprocating arrangement of a pair of sizing heads, each of which includes an opposing pair of upper and lower platens, and a die which is apertured to receive the upper and lower platens therethrough. The meat to be portioned, such as a poultry breast butterfly, is received on the lower platens, and the upper platens are extended downwardly toward the lower platen to compress the meat therebetween. The die then is moved downwardly over the upper and lower platens, with any of the meat extending over the margins thereof being sheared between the inner walls of the die apertures and the outer walls of the lower platens.
Although the described arrangement achieves some degree of consistency as to portion size and thickness, it has been observed to result is less than a 95% separation efficiency as between the portion and the trim. Each cut therefore often must be hand trimmed to attain an acceptable profile. It is speculated that the shearing action developed between the walls of the die apertures and lower platens is insufficient to effect a complete separation of the muscle tissue from the fascia in which it is enveloped.
In view of the foregoing, it will be appreciated that improvements in meat processing, and particularly in the production of an apportioned meat product having a controlled size and weight would be well-received by industry. Especially desired would be the capability to control the size, including thickness, and weight of a poultry product such as the whole muscle chicken breast increasingly favored by consumers as a healthier substitute for hamburger.